While remodeling I had open cell sprayed into my vaulted ceiling. Company convinced me to use open over closed cell. I cant stop thinking about my roof rotting away. I am in climate 4 close to climate 5. The installer told me not to put plastic on the bottom of the rafter. I am from climate 6 where we always use a vapor barrier under drywall. My vaulted ceiling used to be vented. Shouldn't I at the very least remove the ridge cap and close the 1" gap with tar paper and shingles? Do I need to close the air gaps in the soffit? In zone 4, he said the vapor barrier needs to be on the roof side not the house side. Thanks, Confused in MO

I live in lower Michigan and didn't but any vapor barrier but used the new Vapor Barrier Paint from Sherwin Williams.

We have trusses and spray foamed the dry wall to the trusses(this glued the trusses better to the wood to minimize drywall cracking and also sealed really good) Then did R80 blown in fiber glass.

I feel if water gets into wall in our climate it is going to be from in the house unless there is a roof leak. So I wanted to stop it before even getting into the drywall. We are dry 2/3's of the year and we have to add moisture to the house during that time.

Your climate should be damper then ours so make your own decision but I do believe to have a vapor barrier in only one place.